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EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

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Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#41

Post by bitwize »

josephcsible wrote: post #39
kmeisthax wrote: post #11

Earlier quoted context omitted.

The primary purpose of content encryption tools is to trigger DMCA 1201 anti-circumention provisions to prohibit people from writing decryption tools. Nothing more and nothing less. All DRM schemes are a form of obfuscation; some particularly secure ones use hardware decoding enclaves not present on desktops that are harder to crack, but that's about it. The only practically useful DRM schemes are ones where any tool…

> the first prohibits you from circumventing ANY technological measure (yes, even something as simple as a right-click blocker, domain lock, Youtube's rolling URL cipher, or what have you) The law does say it has to be "effective".

The law provides a definition of "effective" which has nothing to do with actual effectiveness in practice. To be effective protection under the DMCA, all that needs to happen is that it provides some restriction of access "in the normal course of its operation". Getting around these access restrictions may well be trivial -- but it's also a felony under federal law punishable by up to five years in prison!

Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#42

Post by grishka »

vengefulduck wrote: post #34
grishka wrote: post #26

Earlier quoted context omitted.

Thanks for linking this talk, it was indeed interesting. Especially the part where he said that "if the hack costs more than 10 games, we're fine". Indeed, you probably aren't breaking this thing unless you have millions of dollars worth of equipment and the expertise to use it. But then video game consoles are special. They were always these closed, tightly-controlled ecosystems. General-purpose devices, like phones…

Intel SGX?

I've seen this name but still don't understand where's its root of trust. In other words:

- How does the program making use of it make sure it's not been patched so the code that's supposed to run in the enclave runs without one?

- How does it know it's not being run on an emulated CPU or in a VM? And that those checks haven't been patched out, too?

- How does it make sure the OS is cooperating? I assume there is some cooperation required from the kernel at least.

Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#43

Post by grishka »

Mindwipe wrote: post #38
grishka wrote: post #18

Earlier quoted context omitted.

> which would get swiftly revoked once public And then what happens to all those devices people bought and expect to be able to watch Netflix on?

They get downgraded to SD.

And then they keep wondering why people pirate...

Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#44

Post by grishka »

bitwize wrote: post #32
grishka wrote: post #10

Earlier quoted context omitted.

IMO it isn't that hard to crack a DRM system. My understanding is that most of the protections are legal, not technical, as in, if you do it, they'll sue the hell out of you and win.

"Eventually, all DRM will be cracked" LOL. Gerhard Lengeling would like a word. He spent as much time implementing the copy protection for Notator as he did writing the program itself, which copy protection involved a dongle in the Atari ST's cartridge port. And despite crackers' best efforts, it remained uncracked for at least two decades.

Also how long did it take to crack the NES CIC chip? But they did crack it in the end.

Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#45

Post by kmeisthax »

shmerl wrote: post #35
kmeisthax wrote: post #31

Earlier quoted context omitted.

DMCA 1201 is a treaty implementation and thus cannot be repealed without significant international backlash.

Treaties can't force unconstitutional garbage, especially when passed in a corrupt undemocratic fashion: https://www.eff.org/deeplinks/2013/03/ustr-secret-copyright-... DMCA 1201 should be repealed hard and never allowed back. Other countries will only thank US for being the first to dump it, even if it will anger DRM proponents who like to write such corrupt laws.

There is a pending legal challenge to parts of DMCA 1201 being spearheaded by the EFF (Green v. DOJ) but I have no idea if it'll actually pass. I hope it does, as there is a legitimate conflict in law between free speech rights and DMCA 1201's restriction on circumvention tools. However, that doesn't mean they're automatically unconstitutional. It just means that strict scrutiny applies. That means it's constitutional if-and-only-if:

1. The restriction is necessary to a "compelling state interest"; 2. The restriction is "narrowly tailored" to achieving this compelling purpose; and 3. The restriction uses the "least restrictive means" to achieve the purpose.

So, I can give you some spoilers: copyright is explicitly mentioned and authorized by the US Constitution, it even gets it's own separate clause. That means copyright is automatically a compelling state interest, and it follows that if we have code that enforces the law, we also have a compelling state interest in protecting that code, too. The EFF's case (and, more generally, any constitutional challenge to DMCA 1201) is going to hinge on the 2nd and 3rd questions of the strict scrutiny test - could they reach the same goal of automated copyright enforcement with a narrower, less restrictive law?

Regarding your particular objections to treaty negotiation, the WIPO Copyright Treaty's undemocratic negotiation process is immaterial to constitutional questions. This is because the US Constitution is explicitly opposed to that. It says the President negotiates treaties and the Senate consents to them. It provides no provision for further democratic control in international relations. In other words, international law is inherently and constitutionally undemocratic. Think about what it means for that to NOT be the case: we'd need every treaty to have a corresponding election in which the citizens of both countries have an up-or-down vote. Very few treaties work this way; the EU sits comfortably at top-of-mind but that's about it.

Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#46

Post by kmeisthax »

josephcsible wrote: post #39
kmeisthax wrote: post #11

Earlier quoted context omitted.

The primary purpose of content encryption tools is to trigger DMCA 1201 anti-circumention provisions to prohibit people from writing decryption tools. Nothing more and nothing less. All DRM schemes are a form of obfuscation; some particularly secure ones use hardware decoding enclaves not present on desktops that are harder to crack, but that's about it. The only practically useful DRM schemes are ones where any tool…

> the first prohibits you from circumventing ANY technological measure (yes, even something as simple as a right-click blocker, domain lock, Youtube's rolling URL cipher, or what have you) The law does say it has to be "effective".

"effective" means "having the effect of", not "is capable of doing".

Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#47

Post by shmerl »

kmeisthax wrote: post #45
shmerl wrote: post #35

Earlier quoted context omitted.

Treaties can't force unconstitutional garbage, especially when passed in a corrupt undemocratic fashion: https://www.eff.org/deeplinks/2013/03/ustr-secret-copyright-... DMCA 1201 should be repealed hard and never allowed back. Other countries will only thank US for being the first to dump it, even if it will anger DRM proponents who like to write such corrupt laws.

There is a pending legal challenge to parts of DMCA 1201 being spearheaded by the EFF (Green v. DOJ) but I have no idea if it'll actually pass. I hope it does, as there is a legitimate conflict in law between free speech rights and DMCA 1201's restriction on circumvention tools. However, that doesn't mean they're automatically unconstitutional. It just means that strict scrutiny applies. That means it's constitutiona…

Problem with DMCA 1201 is that it's not even about copyright. It's about forbidding breaking DRM, which can have cases that have nothing to do with copyright (i.e nothing is infringed by breaking it).

So whatever was authorized for copyright, can't just automatically legitimize DMCA 1201 which is an overreaching prohibition (which is ironic, since what makes DRM itself unethical is that it's an overreaching preemptive policing).

If DMCA 1201 just forbade breaking DRM for copyright infringement, then it could be different. But it's not doing that, so it has to be repealed.

> the WIPO Copyright Treaty's undemocratic negotiation process is immaterial to constitutional questions.

This is important for showing the corrupt nature of both DRM proponents and policy around DRM. It is undemocratic to use treaties as a backdoor to control legislative process. It's simply corruption. And if it's the nature of treaties to be undemocratic, then there should be even a stronger to push against using them to subvert legislation.

Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#48

Post by kmeisthax »

shmerl wrote: post #47
kmeisthax wrote: post #45

Earlier quoted context omitted.

There is a pending legal challenge to parts of DMCA 1201 being spearheaded by the EFF (Green v. DOJ) but I have no idea if it'll actually pass. I hope it does, as there is a legitimate conflict in law between free speech rights and DMCA 1201's restriction on circumvention tools. However, that doesn't mean they're automatically unconstitutional. It just means that strict scrutiny applies. That means it's constitutiona…

Problem with DMCA 1201 is that it's not even about copyright. It's about forbidding breaking DRM, which can have cases that have nothing to do with copyright (i.e nothing is infringed by breaking it). So whatever was authorized for copyright, can't just automatically legitimize DMCA 1201 which is an overreaching prohibition (which is ironic, since what makes DRM itself unethical is that it's an overreaching preemptiv…

What you're describing is the actual state of the law regarding DMCA 1201. DRM only gets legal force when it has the effect of controlling access to a copyrighted work. This has been court-tested: Lexmark v. Static Control Components proves that you cannot legally enforce DRM that does not control access to copyrighted works. You can't copyright ink, ergo you can't argue that ink DRM is protected by DMCA 1201.

That's probably the only reason why DMCA 1201 would pass a strict scrutiny test at all - it's evidence of narrow tailoring.

BTW, what you're describing with treaties has a name: it's called policy laundering.

Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#49

Post by shmerl »

kmeisthax wrote: post #48
shmerl wrote: post #47

Earlier quoted context omitted.

Problem with DMCA 1201 is that it's not even about copyright. It's about forbidding breaking DRM, which can have cases that have nothing to do with copyright (i.e nothing is infringed by breaking it). So whatever was authorized for copyright, can't just automatically legitimize DMCA 1201 which is an overreaching prohibition (which is ironic, since what makes DRM itself unethical is that it's an overreaching preemptiv…

What you're describing is the actual state of the law regarding DMCA 1201. DRM only gets legal force when it has the effect of controlling access to a copyrighted work. This has been court-tested: Lexmark v. Static Control Components proves that you cannot legally enforce DRM that does not control access to copyrighted works. You can't copyright ink, ergo you can't argue that ink DRM is protected by DMCA 1201. That's…

> DRM only gets legal force when it has the effect of controlling access to a copyrighted work.

But that's not what DMCA 1201 is about though, it's just a trick it's using. It's about forbidding DRM breaking [on a copyrighted work]. What if breaking DRM has no bearing on the copyright itself? I.e. it doesn't affect it because nothing is infringed. DMCA 1201 still forbids it. So it's clear that it's wider than simply being about copyright and that's exactly the problem with it - being overreaching and forbidding perfectly legal things that copyright should have no business touching.

DRM proponents realize it very well, and they abuse DMCA 1201 to extend copyright law into any area they want, as long as they can slap any kind of copyright + DRM on it. It basically gives them a rogue lawmaking tool that doesn't need to involve actual legislators.

Like for example forbidding one to switch mobile carriers because it involves breaking DRM. Nothing really to do with copyright - it's about controlling the market. But they use DCMA 1201 for it.

So DMCA 1201 is utter garbage and it's not only corrupt, it's clearly easily abused.

> BTW, what you're describing with treaties has a name: it's called policy laundering.

Yep, that's exactly the origins of DMCA 1201, so I'm always surprised when anyone tries to defend such clearly corrupt law. That's basically being proponents of corruption.

Re: EME, CDM, AES, CENC, and Keys – Building Blocks of DRM

#50

Post by account42 »

bitwize wrote: post #33
shmerl wrote: post #2

That's a good breakdown of how much effort is spent on unethical application of technology. But advertising DRM on the site: "buy DRM"? That's already disgusting.

If you know anyone involved in creative work, you would bite your tongue before saying DRM is unethical. Such people universally, to a man (or woman) believe that unauthorized distribution of their output is unethical because it makes them unable to make money for all their hard work. Inasmuch as DRM prevents this, it is a boon to these people. DRM is a part of life now. Without it, you would not be able to enjoy the…

> DRM is a part of life now.

So is piracy^Wcopyright infringement.

> Without it, you would not be able to enjoy the rich variety of content available on today's internet.

Why not?

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